scripts: emit JSONL for -output json; plain newline only for text

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

scripts/oq

@@ -110,9 +110,14 @@ for i in $(seq 0 $((parallel - 1))); do
         esac
     done
 
-    [ "$parallel" -gt 1 ] && printf '=== %s ===\n' "$id"
-    cat "$B/result" 2>/dev/null
-    printf '\n'
+    if [ -n "$output" ]; then
+        printf '{"session":"%s","result":%s}\n' "$id" \
+            "$(cat "$B/result" 2>/dev/null | jq -Rs .)"
+    else
+        [ "$parallel" -gt 1 ] && printf '=== %s ===\n' "$id"
+        cat "$B/result" 2>/dev/null
+        printf '\n'
+    fi
 
     [ "$keep" -eq 0 ] && rm -r "$B" 2>/dev/null || true
 done